Observation of a Centrality-Dependent Dijet Asymmetry in Lead-Lead Collisions at sqrt(S(NN))= 2.76 TeV with the ATLAS Detector at the LHC

G. Aad...[et al.], Mogens Dam, John Renner Hansen, Jørgen Beck Hansen, Jørn Dines Hansen, Peter Henrik Hansen, Morten Dam Jørgensen, Esben Bryndt Klinkby, Stefania Xella

584 Citations (Scopus)

Abstract

By using the ATLAS detector, observations have been made of a centrality-dependent dijet asymmetry in the collisions of lead ions at the Large Hadron Collider. In a sample of lead-lead events with a per-nucleon center of mass energy of 2.76 TeV, selected with a minimum bias trigger, jets are reconstructed in fine-grained, longitudinally segmented electromagnetic and hadronic calorimeters. The transverse energies of dijets in opposite hemispheres are observed to become systematically more unbalanced with increasing event centrality leading to a large number of events which contain highly asymmetric dijets. This is the first observation of an enhancement of events with such large dijet asymmetries, not observed in proton-proton collisions, which may point to an interpretation in terms of strong jet energy loss in a hot, dense medium.
Original languageEnglish
JournalPhysical Review Letters
Volume105
Issue number25
Pages (from-to)252303
Number of pages18
ISSN0031-9007
DOIs
Publication statusPublished - 13 Dec 2010

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